How to Choose a Manufacturing Method for Your Thin Metal Part
Your project or device calls for a thin metal part to be produced. Maybe it’s an EMI shield, a precision aperture, a fluidic plate, or a battery component. Perhaps it is a prototype or production scale part. Thickness somewhere between 0.001″ and 0.040″. The geometry is mostly 2D-derived, possibly with a forming step. Now you have to decide how to make it.
This guide compares six manufacturing methods used for thin metal parts: photochemical etching, stamping, laser cutting, CNC machining, wire EDM, and metal 3D printing. The goal is to help you match the method to the part: tolerance, material, volume, geometry, lead time. Each has its strengths and weaknesses.
The decision factors
Engineers tend to evaluate thin metal manufacturing on a consistent set of factors. Some matter more than others depending on the part. The factors below are the ones that actually drive method selection.
Part Geometry
Part geometry. Most thin metal parts are 2D-derived: flat features, holes, slots, contours, etched lines. Some require forming, bending, or coining as a secondary step. Truly 3D geometry (deep pockets, complex internal volumes) usually points away from sheet processes and toward machining or additive.
Material thickness
For thinner materials, many traditional processes start to struggle. Stamping deforms thin material. Laser cutting introduces a heat-affected zone that becomes a larger fraction of the part. CNC machining causes deflection. The sub-0.010″ range is photochemical etching territory.
Tolerance requirements
Each method has an achievable tolerance range that depends on thickness and feature size. Tighter tolerances often mean slower, more expensive processes, or post-processing.
Volume
Prototype, low volume (hundreds), mid volume (thousands), high volume (tens of thousands and up). Volume drives the tooling decision.
Lead time
Two distinct numbers: tooling lead time (how long until you can make the first part) and production lead time (how long once tooling exists). Stamping has long tooling lead and fast production once running. Etching, laser, and EDM have no hard tooling lead.
Tooling cost
Hard tooling is amortized across the production run. Below a certain volume, tooling cost dominates the per-part price. Above it, hard tooling wins.
Edge quality, burr, residual stress, heat-affected zone.
Mechanical processes leave burrs and work-harden the edge. Thermal processes leave a heat-affected zone and a recast layer. Chemical etching leaves a smooth, deformation-free edge with no induced stress. Whether this matters depends on the part: critical sealing surfaces, optical apertures, and fatigue-loaded components are sensitive.
Comparison at a glance
The table below summarizes typical performance by method. Numbers are typical ranges that hold across the thin-metal regime (0.001″–0.040″). For tighter or wider conditions, treat these as starting points and confirm with the manufacturer.
| Method | Thickness range | Tolerance | Tooling | Tooling lead | Production lead | Volume sweet spot | Edge / stress |
| PCM | 0.001″–0.040″ | ±0.001″ typical | Low cost photo tooling | Hours to 1 day | 1–3 days | Prototype to mid; high possible | No mechanical burr, no HAZ, stress-free |
| Stamping | 0.005″–0.250″ | ±0.002″ to ±0.005″ | Hard tooling, high cost | 8–16 weeks | Days at run rate | High volume (10K+) | Burrs, work hardening |
| Laser cutting | 0.005″–0.500″+ | ±0.002″ to ±0.005″ | Hard tooling, high cost | 8–16 weeks | 1–2 weeks | Prototype to mid | HAZ, recast layer on thin sheet |
| CNC machining | 0.005″+ (thin sheet difficult) | ±0.0005″ possible | Fixturing only | Days | 2–4 weeks | Prototype to low | Burrs, possible deflection on thin sheets |
| Wire EDM | 0.005″ to several inches | ±0.0001″ to ±0.0005″ | None | None | 1–3 weeks | Prototype to low | Recast layer, slow process |
| Metal AM / 3-D printing | Feature-dependent, ~0.010″ minimum | ±0.005″ typical | None | None | Days to weeks | Prototype, very low volume | As-built surface, post-processing required |
Note: Numbers are typical ranges, not guarantees. Specific capability depends on shop, material, and part design.
Photochemical etching (PCE)
Photochemical etching, also known as photochemical machining (PCM), removes metal selectively using a photoresist mask and a controlled etchant. The result is a flat metal part with smooth, deformation-free edges and no induced stress.
PCE excels in the 0.001″–0.040″ thickness range, where complex 2D geometries (fine grids, mesh, narrow slots, intricate apertures) are routine and where most other methods either deform the material or leave problematic edges. Tolerances of ±0.001″ are typical. The process holds up across a wide material set, including specialty alloys that mechanical and thermal processes struggle with: Mu Metal, Kovar, Invar, molybdenum, beryllium copper, Havar, Nitinol, Permalloy 80, Metglas, and many others.
PCE struggles when geometry becomes truly 3D, when material is thicker than about 0.060″ (achievable but slower and at wider tolerance), or at very high volumes where amortized stamping tooling beats it on per-part cost. But multiple thin etched sheets can be fused into 3D components using diffusion bonding.
When to use: thin specialty alloys, complex 2D features, prototype-to-mid volume, parts where edge quality and zero residual stress matter (sealing, optical, fatigue-critical).
When to avoid: simple geometries at very high volume, true 3D parts.
Deeper detail: Precision Chemical Etching
Metal stamping
Metal stamping forms parts by pressing sheet metal between hardened dies. It is a high-volume process with a high tooling investment up front.
Stamping excels at high-volume runs (tens of thousands and up) on relatively simple geometries. Once tooling is paid for, per-part cost is low and production is fast, but tool wear may require periodic refurbishment and replacement. Material thickness is typically 0.005″ to 0.250″.
Stamping struggles below 0.005″ because the material deforms. It struggles with intricate internal features that hard tooling cannot reproduce, and at low volumes where tooling cost dominates. It also leaves burrs and work-hardens the cut edge, which can be a problem for sealing surfaces or fatigue-critical parts.
When to use
High-volume runs, established designs, robust geometries.
When to avoid
Prototypes, design-iterative work, very thin or complex parts, parts sensitive to edge condition.
Deeper detail
Laser cutting
Laser cutting uses a focused beam to vaporize or melt a kerf through the material. It needs no hard tooling and is fast to set up.
Laser cutting excels at flat sheet parts in the 0.020″–0.500″ range, with quick turnaround and reasonable accuracy. It is a workhorse for medium-tolerance flat parts in common materials.
On thin sheet (below about 0.010″), or with features in close proximity, laser cutting becomes difficult. The heat-affected zone and recast layer become a large fraction of the part, the kerf width limits feature density, and thermal stress can cause deformation. Reflective materials like copper and brass and some specialty alloys are also harder to cut cleanly.
When to use
Medium-thickness flat parts, prototype to mid-volume, common materials.
When to avoid
Very thin material, dense feature patterns, parts that cannot tolerate a heat-affected zone.
CNC machining
CNC machining removes material with a rotating tool against a fixtured workpiece. It produces parts at very tight tolerance with full 3D capability.
Machining excels at 3D geometry, tight tolerances (±0.0005″ achievable), and material flexibility. It is the right answer for blocks, brackets, housings, and other parts with depth.
On thin sheet, machining gets hard. Workpiece deflection becomes a problem below about 0.020″. Cutting forces deform the part. Fixturing thin material reliably is its own engineering challenge. Burrs are common and need post-processing. Tooling and setup time also limit it to lower volumes.
When to use
3D parts, very tight tolerance on solid stock, low-volume precision.
When to avoid
Thin sheet (under 0.020″), high-volume flat parts, dense intricate features.
Wire EDM (electrical discharge machining)
Wire EDM cuts conductive materials using electrical sparks between a thin wire electrode and the workpiece. It produces extremely tight tolerance with no mechanical force.
EDM excels at very tight tolerance (±0.0001″ achievable), hardened materials that resist machining, and intricate internal contours that traditional cutting cannot reach. Material thickness can range from 0.005″ to several inches.
EDM is slow, especially on thin material where the per-square-inch removal rate is the limiting factor. The recast layer left by spark erosion can be problematic for some applications. Cost per part is high, which restricts EDM to prototypes and low-volume precision work.
When to use
Very tight tolerance, hardened materials, intricate internal features, low volumes.
When to avoid
Production runs, parts where the recast layer matters, simple geometries that cheaper methods handle.
Deeper detail
Metal 3D printing (additive manufacturing)
Metal additive manufacturing builds parts layer by layer from powdered metal, typically using laser or electron-beam fusion. It excels at geometric freedom that no subtractive process can match.
3D printing handles internal channels, lattice structures, conformal cooling, and consolidated assemblies. It produces geometry that would otherwise require multi-part fabrication. It is a strong fit for low-volume, complex 3D parts where traditional manufacturing would require complicated tooling or diffusion bonding of multiple layers.
For thin sheet-style parts, 3D printing is usually the wrong tool. Minimum feature size is around 0.010″, surface finish is rough as-built and needs post-processing, tolerances of ±0.005″ are typical, and per-part cost is high. The material set is more limited than thin-metal etching, with most printable alloys being structural rather than specialty.
When to use
Complex 3D geometry, internal features, low-volume parts that would otherwise require assembly.
When to avoid
Thin flat parts, specialty alloys, mid- to high-volume runs.
Deeper detail
Decision Guidance
A few patterns hold across most thin-metal manufacturing decisions.
- Start with thickness.
If your part is below 0.005″, photochemical etching is almost always the right answer. Stamping deforms, laser leaves too much HAZ relative to part size, machining deflects, EDM is slow, additive cannot reach the feature size. - For 0.005″–0.040″ with complex features, etching usually wins on geometry.
Fine slots, narrow webs, and dense feature patterns reproduce cleanly because the photo mask carries the geometric complexity, not a cutting tool. No tool means no minimum feature radius beyond what the photoresist resolves. - Volume drives the tooling question.
Below about 10,000 parts a year, hard tooling for stamping rarely amortizes. Above 50,000, stamping usually beats etching on per-part cost. The middle ground depends on geometry and material: etching often holds longer for complex parts and specialty alloys. - Specialty alloys narrow the field.
Mu Metal, Kovar, Invar, molybdenum, beryllium copper, Havar, Nitinol, and similar materials are routine for photochemical etching but problematic for laser, stamping, and additive. If your part is in this material set, etching is usually the only thin-metal option without significant compromise. - If your part is truly 3D, look at machining, additive, or diffusion-bonded etched stacks.
Machining and additive cover monolithic parts. Bonded etched stacks cover layer-built structures. - If edge condition matters (sealing, fatigue, optical), prefer chemical or fine-EDM processes over mechanical and thermal cutting.
Burrs, recast layers, and heat-affected zones all show up in the application eventually.
The decision rarely comes down to one factor. It is the combination: thickness, material, geometry, volume, edge requirement. Pick the method that fails the fewest of those constraints.
Where Fotofab fits
Fotofab is a photochemical etching expert. The method we know best is the one we lead with above. We work with engineers across aerospace, defense, medical, photonics, semiconductor, test and measurement, and electronics, on parts in the 0.001″–0.040″ range across more than 24 standard and specialty alloys.
In-house, we run photochemical etching, metal forming, finishing, and partial assembly. We also offer diffusion bonding services for multilayer etched stacks (used in heat exchangers, fuel cell plates, microfluidic structures, and similar bonded assemblies); the bonding step is performed through a qualified partner and presented single-source to the customer. For complex multi-process assembly outside our standard scope, we work case by case.
Our material set is the differentiator most engineers care about. Standard metals (aluminum, stainless steel, copper, brass, nickel, inconel, titanium) sit alongside the specialty alloys most thin-metal shops do not handle: Mu Metal, Kovar, Invar, molybdenum, Permalloy 80, Metglas, Nichrome, nickel silver, copper-nickel, phosphor bronze, Alloy 42, Alloy 48, Monel, spring steel, tungsten-copper.
Fotofab is AS9100D certified, ISO 9001:2015 registered, and ITAR registered. Full certifications detail here. We deliver parts in 1–3 days from a digital file, with no hard tooling. For volume work, the same process scales without changing the part.
We are not a fit for every part or design. If your design points cleanly to stamping or machining or additive, that is the right answer and we will say so.
In short
The right manufacturing method depends on the part, not the brand making the case. For thin metal parts, the realistic choices are photochemical etching, stamping, laser cutting, CNC machining, wire EDM, and metal 3D printing. Each fits a different region of the decision space.
Deeper comparisons:
- Photochemical etching vs metal forming
- Photochemical etching vs laser cutting
- Photochemical etching vs 3D printing
- Photochemical etching vs CNC machining
